In my U.S. Pat. No. 3,905,623, a pipe coupling is disclosed in which a wide-band sleeve is stretched over adjoining pipe ends to provide a mechanical connection with a fluid seal between the pipes. In this patent, the coupling includes a sleeve having a roundish sector and a channel-shaped sector and force applying means connected with the channel-shaped sector is adapted to stretch the sleeve to form the joint. A pipe coupling which is similar but especially adapted for lap joints is shown in my U.S. Pat. No. 4,056,273. The couplings of my aforementioned patents utilize a closed sleeve which must be installed by putting one of the pipe ends through the sleeve.
U.S. Pat. No. 3,944,265 to Hiemstra, et al. discloses a pipe coupling which comprises a sheet metal band provided with reenforcing plates at each end with bolts extending through the plates to draw the plates together and stretch the band around the pipe ends. The sheet metal band of this coupling assumes the form of a flat strip or sheet prior to installation and must be wrapped around the pipe ends. The coupling of this patent has the disadvantage of stress distribution in the band which is highly non-uniform with a high degree of stress concentration in the vicinity of the reenforcing plate.
It is the general object of this invention to provide a pipe coupling having the advantages of a stretched wide-band sleeve and an open sleeve to facilitate installation on pipes which are already butted or telescoped together.